Surface ornamentation for a lunch case



FIG. 1 is a front elevation view of a surface ornamentation for a lunch case showing my new design;

FIG. 2 is a bottom plan view thereof;

FIG. 3 is a left side elevation view thereof;

FIG. 4 is a right side elevation view thereof; and,

FIG. 5 is a top plan view thereof.

The broken lines showing the lunch case are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a surface ornamentation for a lunch case, as shown and described. 